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[Nemo]

I was reading an old (1976) Ripmax catalogue and came across this advert. Long before I started ship models, but I wondered if anyone here has ever used one and what the performance was like.

[essex2visuvesi]

I have one


New in Box that I bought on ebay.... just because (and the fact that I am a big fan of rotary engines) :)
One day I will build something to run it in 


There are some nice videos on Youtube of the OS rotary in action

[Martin (Admin)]

I've heard, very fast, quite powerful, very noisy!

[Jonty]

  I had an NSU Ro80 when I was in the motor trade. Very impressive by the standards of the day. As I recall it, the clutch was actuated by a microswitch in the gearknob - all you had to do was move the lever. And remember not to rest your hand on the knob! The engine was very smooth, but the oil consumption was frightening, and I was relieved when I passed it on a week or two later. Unfortunaely, the girl didn't come with the car...

[Jonty]

  On a more serious note, googling "miniature Wankel engine" brings up some interesting stuff.

[essex2visuvesi]

http://www.ebay.co.uk/itm/O-S-MAX-30-WANKEL-ENGINE-WITH-MUFFLER-/121822606598


if you fancy one
Spares are not easy to find, which is partly why mine is still in the box lol

[Perkasaman2]

I recall that calculating the swept cubic capacity of these engines was quite a headache.

[Martin (Admin)]

  I had an NSU Ro80 when I was in the motor trade. Very impressive by the standards of the day. As I recall it, the clutch was actuated by a microswitch in the gearknob - all you had to do was move the lever. And remember not to rest your hand on the knob! The engine was very smooth, but the oil consumption was frightening, and I was relieved when I passed it on a week or two later. Unfortunaely, the girl didn't come with the car...

Is there a car in that photo?!?!

[Colin Bishop]

I've heard that the big problem with the Wankels is the seals between the rotor and the casing which were responsible for the high oil consumption and low mpg. A case of the technology not keeping up with the concept? Was this also a problem with the model version?

Colin

[JimG]

I had and flew one, it's high revving and is quiet running. It only needs a small silencer as there is not the same pulsing as the exhaust on a two stroke, more a continuous exhaust, gives a strange noise when running.. The biggest problem is it's thirsty, equivalent size to a .30 with the power of a .40 and the thirst of a .60. Because of the high fuel use it throws out a lot of oil most of which found its way onto the side of the model. At that time I was usaing mostly castor based fuel so clean up at the end of the day was not fun. With more modern synthetic fuels it might need less cleaning. Unfortunately the front bearing failed (castor hardened in storage ) and the rotor hit the combustion chamber damaging it so the engine is now dead. The seals worked well in the model and showed little signs of wear after running.

Jim

[Plastic - RIP]

I've never owned a rotary engined car - always fancied the RO80 but the warranty claims on the engine killed the company. You can see the design team's influence in the later Audi 80 which is basically what the RO80 design became.

I've been coveting an RX8 (they are VERY cheap now but the engines are either knackered or just about to fail). The problems are all to do with the oil pressure relief valve letting by too soon so at low revs, there is oil starvation.  The company that rebuilds them solve the oil flow problem but it means taking the engine to bits. 

There are 3 stages of engine rebuild available to keep these on the road - £2000 for a basic cheapo rebuild re-using most of the parts - not reccommended, £2500 for a minimal rebuild and £3000 for a proper rebuild.

In typical British traffic jams, the engine eats itself but in European motorway driving, the engine lives longer. It needs to be thrashed to keep the oil flowing. The rebuild makes that problem go away.

[jarvo]

Hi plastic


Guy at work has one that has been worked on, your right, goes like stink, with the rebuild and an up rated turbo, sadley the inner wings have gone and he cant afford the body rebuild, sat on his drive now, such a pity, rest of the car is in superb condition


Mark

[Plastic - RIP]

Hi plastic


Guy at work has one that has been worked on, your right, goes like stink, with the rebuild and an up rated turbo, sadley the inner wings have gone and he cant afford the body rebuild, sat on his drive now, such a pity, rest of the car is in superb condition


Mark

Yes - They are all sat on drives now - look on ebay - they're all 'spares or repair' with dead engines. If the engine has actually failed, the bill could be MUCH higher than £3000.

Unfortunately, an actual working/MOTed, usable RX8 is realistically worthless when there is a £3000 bill just around the corner and the engine could have a catastophic failure with no warning. Sadly, the owners of these cars think they are worth thousands.


Just too risky.

I was hoping Wheeler Dealers would pick one up and get Ed to do an engine rebuild to see if it's possible for the average mechanic at home.

[essex2visuvesi]

I was hoping Wheeler Dealers would pick one up and get Ed to do an engine rebuild to see if it's possible for the average mechanic at home.

yes it is possible, its easier than a traditional piston engine far fewer parts


My RX8 is in regular use.
The problem with the RX8 is that Mazda tried to market its a mainstream sports coupe, and therefore owners treated them like a mainstream car...... Poor servicing, the wrong type of oil and misinformation from "the man in the pub" led to what we have today.
The rotary engine needs more care with the warm up cycle than a normal piston engine.
The the engine injects oil from the sump into the combustion cycle so it needs an oil that burns. Something that modern synthetics do badly.  This means that many cars were run on what the owner "thought" was the best oil, which then proceeds to gum up the seals with partially burned oil.  this in turn leads to premature engine failiure
I have modified my car to inject the oil into the engine (Sohn adaptor) from a separate container rather than the sump.  this means I can use 2 stroke oil to inject into the engine while protecting the bearings with high quality fully synthetic oil


In order to fully appreciate the RX8 or any rotary for that matter you need to drive one.

[Plastic - RIP]

yes it is possible, its easier than a traditional piston engine

how is it easier? Pistons, rings, bores & cranks can be re-finished anywhere - the rotor and its chamber are not easily set up on a mill to get a precision fit.
I used to have my guys rebuild rotary vacuum pumps (similar problems) and even with the proper rebuild kits the results were not always successful.

[essex2visuvesi]

Hi plastic


Guy at work has one that has been worked on, your right, goes like stink, with the rebuild and an up rated turbo, sadley the inner wings have gone and he cant afford the body rebuild, sat on his drive now, such a pity, rest of the car is in superb condition


Mark

As plastic has said he can pick up a good condition RX8 with a blown engine for less that 800 quid and dump his mechanicals into it
considering that if it is turbocharged as you say then the conversion probably cost 10 times that much then its worth doing

[essex2visuvesi]

how is it easier? Pistons, rings, bores & cranks can be re-finished anywhere - the rotor and its chamber are not easily set up on a mill to get a precision fit.

there you go
you have answered your own question.
Far fewer parts


Have a look on youtube and you will see many rotary rebuild videos

[Brian60]

I had a test ride on a Norton twin rotary way back in the 70's. It was the smoothest motorcycle I have ever ridden, and the power delivery was so linear. Like all rotary's  back then they suffered the usual problem of rotor tip wear. However that isn't the case nowadays, with the advancement in ceramic technology it is no longer a problem. I seem tor recall that there was a rotary engine running in last years LeMans, but for the life of me I can't remember the manufacturer, although Mazda is the modern day builder of such engines.

[TheLongBuild]

Is there a car in that photo?!?!

Yes, It is blocking the great rock formation in the background..

[essex2visuvesi]

I had a test ride on a Norton twin rotary way back in the 70's. It was the smoothest motorcycle I have ever ridden, and the power delivery was so linear. Like all rotary's  back then they suffered the usual problem of rotor tip wear. However that isn't the case nowadays, with the advancement in ceramic technology it is no longer a problem. I seem tor recall that there was a rotary engine running in last years LeMans, but for the life of me I can't remember the manufacturer, although Mazda is the modern day builder of such engines.

Last year?


Johnny Herbert won with the 787B in '91
To date still the only Japanese manufacturer to win Le Mans

[Brian60]

yep last year essex. It wasn't running in LMP1 or LMP2 classes though, I think it was in in GTE am the lowest sportsman class.

[Jonty]

  There was a lot of excitement when the Ro80 came out - there was limited production predecessor based on the smaller Prinz- as it seemed to be the way forwards. Rolls-Royce actually took out a licence from Wankel, but apparently they intended to use it as a supercharger rather than as an engine. Never heard any more about that.

[essex2visuvesi]

Rolls Royce also developed at a diesel rotary

[tr7v8]

Rotaries running on diesel are used as APUs on aircraft.
The issue with the RO80 was there was no revlimiter just a buzzer so people revved them to destruction.